This relates to imaging systems and, more particularly, to imaging systems with column randomizing circuits.
Modern electronic devices such as cellular telephones, cameras, and computers often use digital image sensors. Imagers (i.e., image sensors) may be formed from a two-dimensional array of image sensing pixels. Each pixel receives incident photons (light) and converts the photons into electrical signals. Image sensors are sometimes designed to provide images to electronic devices using a Joint Photographic Experts Group (JPEG) format.
Typical image sensors include multiple identical sets of image readout circuits. Each image readout circuit is connected to a single column of pixels in the image sensor. Consequently, each pixel in a particular column is read out by a single image readout circuit. Differences between the image readout circuits result in column-wide image offsets (i.e., fixed pattern column noise). Image sensors implementing this type of arrangement therefore produces images with undesirable fixed pattern noise, which is more readily observed by a user than random noise.
It would therefore be desirable to provide improved imaging systems with column randomizing circuits.